Electrical or electronic components, for example semiconductor chips, are soldered into housings for the purposes of electrical contact, for heat dissipation and as a protection against damage. For example, in a known embodiment of a power diode, the silicon chip is fixed between two cylindrical copper parts by soldering. In this case a disk of solder is placed on one copper cylinder, the chip is placed on top of it and subsequently a second disk of solder is applied, on which the other copper cylinder is then placed. The two cylindrical copper parts each have a center depression on which, to prevent lateral dislocation, the relatively easily deformable disks of solder are held after being pressed against them so that the edges of the depressions penetrate the soft solder. In the course of placement of the parts on each other (copper cylinder with disk of solder/chip/copper cylinder with disk of solder) and subsequent soldering in a continuous furnace the said parts are kept together in a magazine (bore of a support body). This is necessary because the parts are being moved on conveyor belts during the production process described above. The conveyor belts are moved at great acceleration between the processing stations to attain high rates of production. Mismatches between the individual parts would occur without the magazines.
Chips with large surfaces (greater than 10 mm.sup.2) are used, particularly in connection with the above mentioned power semiconductor components, to keep losses during operation low and to assure good heat dissipation. It is necessary to form thin solder layers for good heat dissipation (the thickness of the solder layer should be between 20 .mu.m and 60 .mu.m). The heat dissipation is impaired if bubbles (hollow spaces) are created in the soldering process, so that soldering with as few bubbles as possible is the goal. This entails considerable expenditures. The chip surfaces are covered with special oxidation-resistant metal surfaces (gold, silver). The connecting pieces (for example the said cylindrical copper parts) are specially cleaned. Soldering is performed in so-called muffle furnaces in the presence of a reducing gas atmosphere of the highest purity (H.sub.2 or N.sub.2 /H.sub.2).
Bubbles are being observed in the solder layers in spite of all these efforts. These are caused by the entrapment of air between the solder preform and the associated connecting piece. One source for this entrapment of air is the fixing of the solder preform on the connecting piece (component). However, this fixing of the solder preform prior to soldering is necessary in order to prevent the already mentioned mismatch between the connecting piece, the chip and/or the solder preform. The above discussed use of magazines for bringing the components into alignment in relation to each other is insufficient, since because of its small size the solder preform is not guided (aligned) by the magazine. Because it is intended, on the one hand, to create thin layers of solder, but on the other hand the solder preforms of little thickness can no longer be automatically processed because of the easy deformability of the soft solder, it is necessary to make the thickness of a not yet soldered solder preform greater than the thickness of the solder layer which forms later. For this reason the size/diameter of this solder preform is less in the non-soldered state than the size/diameter of the components to be soldered together. For aligning the components in relation to each other, the size of the bore in the magazine corresponds to the diameter of the components. For the above mentioned reasons the solder preform has a lesser diameter so that it cannot be brought into alignment by the wall of the bore. Thus it is necessary to fix the solder preform on one component by means of the described joining prior to soldering in order to prevent lateral displacement. If lateral displacement did occur it would result in wedge-shaped soldering layers of poor quality between the components. The solder preforms are fixed in a centered way on the soldering surfaces of the connecting pieces by the joining operation.
It is known from U.S. Letters Pat. No. 3,860,949, Stoeckert et al., to form straight grooves which are placed parallel next to each other on the soldering surfaces of components. This provides an improvement of the soldered connection; however, the use of such grooves for the simultaneous fixing of solder preforms cannot be found in the cited reference.
Up to now a centered bore (depression) for fixing the solder preform in the component had been formed, so that the bore edges could penetrate into the soft solder preform. It has been found that there is considerable danger of the formation of large bubbles in this connection.